U.S. patent application number 13/495017 was filed with the patent office on 2013-12-19 for serpentine insert for open web grid.
This patent application is currently assigned to USG Interiors, LLC. The applicant listed for this patent is Peder J. Gulbrandsen, James J. Lehane, JR.. Invention is credited to Peder J. Gulbrandsen, James J. Lehane, JR..
Application Number | 20130333317 13/495017 |
Document ID | / |
Family ID | 48652350 |
Filed Date | 2013-12-19 |
United States Patent
Application |
20130333317 |
Kind Code |
A1 |
Lehane, JR.; James J. ; et
al. |
December 19, 2013 |
SERPENTINE INSERT FOR OPEN WEB GRID
Abstract
A grid runner and method of its manufacture that saves material
content with use of a serpentine sheet metal web configured to be
essentially scrapless and that results in a parallel chord
truss-like construction with open spaces between an upper
reinforcing bulb and a lower flange.
Inventors: |
Lehane, JR.; James J.;
(McHenry, IL) ; Gulbrandsen; Peder J.; (Aurora,
IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Lehane, JR.; James J.
Gulbrandsen; Peder J. |
McHenry
Aurora |
IL
IL |
US
US |
|
|
Assignee: |
USG Interiors, LLC
Chicago
IL
|
Family ID: |
48652350 |
Appl. No.: |
13/495017 |
Filed: |
June 13, 2012 |
Current U.S.
Class: |
52/506.06 ;
29/428 |
Current CPC
Class: |
E04C 2003/0439 20130101;
Y10T 29/49826 20150115; E04C 2003/0491 20130101; E04B 9/067
20130101; E04C 3/09 20130101; E04C 2003/0413 20130101; E04C
2003/046 20130101 |
Class at
Publication: |
52/506.06 ;
29/428 |
International
Class: |
E04B 9/18 20060101
E04B009/18; B23P 17/04 20060101 B23P017/04 |
Claims
1. A grid runner for a suspended ceiling comprising an elongated
hollow metal reinforcing bulb having a central depending rib, an
elongated metal flange having a central upstanding rib, and an
elongated sheet metal web having a serpentine profile characterized
by crests and valleys, the crests being fixed to the bulb rib and
the valleys being fixed to the flange rib, the web maintaining the
bulb and flange ribs vertically spaced from one another and
providing open areas between the bulb and flange ribs in areas
below the crests and/or above the valleys.
2. The grid runner as set forth in claim 1, wherein the web is
sheared from sheet metal stock such that an upper edge of the web
has a geometry that is the same as the bottom edge of the web.
3. The grid runner as set forth in claim 1, the web being
constructed of at least two elongated parts joined by overlapping
adjacent ends.
4. A grid runner as set forth in claim 1, wherein the web is fixed
to the bulb and flange with integral clinches.
5. A method of forming a grid runner for a suspended ceiling
comprising supplying a longitudinally extending hollow reinforcing
bulb with a lower depending rib and a longitudinally extending
flange with an upstanding central rib, shearing an elongated
serpentine web from sheet metal coil stock in a manner where the
lengthwise direction of the web is transverse to the direction of
feed of the stock and the web is shaped with a series of crests and
valleys intervening the crests, the upper profile of the web being
geometrically complementary to the lower profile of the web, fixing
the web crests to the depending rib of the bulb and the web valleys
to the upstanding rib of the flange while sections of the web
intermediate the crests and valleys leave open spaces between the
bulb and flange thereby reducing the material content in the runner
for a given weight supporting capacity compared to a grid runner of
conventional construction having a substantially solid web.
6. A method as set forth in claim 5, wherein the crests and valleys
are clenched to the bulb and flange ribs in a manner free of
separate fasteners.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to suspended ceiling grid
construction.
PRIOR ART
[0002] Suspended ceilings typically include a rectangular metal
grid on which are supported ceiling tiles or drywall panels. The
commercial construction industry is highly competitive and,
accordingly, the cost of building materials in this sector is
important. Raw material consumption, particularly material without
a large recycled content, is likewise a concern for preservation of
the environment. Accordingly, there is a need for suspended grid
products that consume less material and can be economically
produced.
SUMMARY OF THE INVENTION
[0003] The invention is embodied in a suspended ceiling grid runner
having a material saving open web construction. The inventive grid
runner is an elongated assembly of main parts comprising a lower
face flange, an upper reinforcing bulb and an open web extending
vertically between the flange and bulb. The web has a novel
serpentine configuration extending alternately from the flange to
the bulb and from the bulb to the flange. The web is fixed to the
flange and bulb at each juncture. By virtue of its serpentine
configuration, the web is characterized by open spaces along the
length of the runner that represent significant material savings.
In the preferred runner construction, the flange and bulb are roll
formed sheet metal strips while the web is a flat, stamped strip.
These components are assembled together in a press that clinches
the parts together at locally overlapping points.
[0004] The web strip is sheared from sheet stock, preferably
supplied from a coil. The shear has specially shaped cutting edges
corresponding to the serpentine form of the web. By way of example
and not limitation, the web sheet stock is fed to a shear in 3/4
in. increments while producing a web 1-3/8 in. high without scrap.
The inventive runner is advantageously assembled in a press
operation that also performs the traditional cross tee slot and
hanger hole punching.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a fragmentary side elevational view of a grid
runner constructed in accordance with the invention;
[0006] FIG. 2 is an end view of the grid runner of FIG. 1;
[0007] FIG. 3 is a cross sectional view of the grid runner taken in
the plane 3-3 indicated in FIG. 1;
[0008] FIG. 4 is a diagrammatic representation of a shearing
process used to make a serpentine web of the inventive grid
runner;
[0009] FIG. 5 is a diagrammatic representation of the assembly of
three web inserts used in the construction of the main runner
embodying the invention; and
[0010] FIG. 6 is a cross sectional view of a typical clinch joint
between the web and the bulb or the flange of the grid runner.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] A grid runner 10, illustrated in FIGS. 1-3, is used in a
conventional manner to construct a rectangular grid for a suspended
ceiling. The illustrated grid runner 10 has the shape of an
inverted tee in the orientation it is used. The grid runner 10,
which typically can have a height in the order of 1- 9/16 in. can
be provided as a main runner and have a nominal length of 12 ft.
The runner 10 is an assembly of three main elongated parts
comprising an upper hollow reinforcing bulb 11, a lower face flange
12, and a vertical web 13 extending between the bulb 11 and flange
12. Identical end connectors 14 are provided on each end of the
runner 10 (only one end is shown in FIG. 1). The connectors 14 may,
for example, be of the type illustrated in U.S. Pat. No.
6,729,100.
[0012] Preferably, the bulb 11 and flange 12 are each made by roll
forming a single sheet metal strip, usually steel, with
conventional techniques well known in the industry. The flange 12
can be pre-painted prior to roll forming on a side visible when
installed. The bulb is hollow with a circular cross section. The
bulb 11 can be formed with various other cross sectional shapes
such as an oval, rectangle, triangle or other polygon. The bulb 11
is preferably formed with the hollow space essentially closed. The
bulb 11 includes a depending rib 16 that lies in a vertical plane
bisecting the hollow part, the latter comprising the bulb
proper.
[0013] The illustrated flange 12 has the shape of an inverted short
tee. In use, the flange commonly becomes the visible face of the
grid runner 10 where the grid runner is used with ceiling tiles. A
horizontal part 18 of the flange 12 extends widthwise, i.e.
transversely to the longitudinal direction of the runner and
symmetrically about a vertical upstanding stem or rib 19. One side
21 of the horizontal flange part 18 is a double wall or two ply
construction while an opposite side 22 is a single wall with a
folded back hem 23 at an edge distal from the rib 19. In ordinary
use of the runner 10 in a suspended ceiling, edges of rectangular
ceiling panels or tiles rest on upper surfaces of the flange
horizontal part 18.
[0014] The web 13 is a flat sheet metal stamping that serves to
hold the bulb 11 and flange 12 in spaced relation in the manner of
a parallel chord truss. Referring to FIG. 4, the web 13 is formed
by shearing a strip from a sheet of steel or other metal 25,
typically from coil stock. The web strip is sheared along a
serpentine line symmetrical with a line that is perpendicular to
the feed direction of the sheet stock indicated by the arrows 26
from the supply coil. Alternatively, the serpentine strip or web
can be sheared from a flat non-coiled sheet stock although this
will involve greater scrap due to cuts at the end of the sheet
stock. The serpentine cut profile of the web 13 is cut such that
its top and bottom edges have the same geometry. This results from
the sheared edge remaining on the stock supply becoming one of the
edges of the next sheared web piece.
[0015] In profile, the web 13 can be described as having crests 31
and valleys 32 that, in the illustrated case, are flat at their
respective top and bottom edges. The serpentine pattern of the web
13 allows the web to span, from the outside edges of the valleys 32
to the outside edges of the crests 31 a distance of 1-3/8 in., for
example, while the stock need only be fed 3/4 in., for example, to
produce this span. When assembled, the web crest flats and valley
flats can abut the bottom of the bulb 11 and top of the single ply
flange side 22, respectively.
[0016] The grid runner 10 is assembled in a press of a length
adequate to span the length of the grid runner. The disclosed grid
runner construction is ideally suited for main runners which are
nominally 12 ft. long or industry metric equivalent. When the
runner 10 is this long, it is practical to use 2 or 3 web sections
33 arranged end to end. Making the full length web 13 from the
sub-parts or sections 33 enables the use of light gauge coil stock
of a conventional width. Preferably, the web sections 33 are
slightly overlapped at their adjacent ends when assembled into a
grid runner 10. FIG. 5 illustrates three web sections 33 with their
adjacent ends aligned to be overlapped and joined in a single main
runner 10.
[0017] With reference to FIG. 1, the web 13 is fixed to the bulb 11
and flange 12 in a press. The web crests 31 are fixed to the bulb
rib 16 and the valleys 32 are fixed to the flange rib 19. FIG. 6
illustrates a typical permanent clinch joint 30 made by a known
technique such as that marketed under the trademark TOX.RTM. (a
registered trademark of Pressotechnik GmbH & Co. KG). The
technique involves lapping these members and driving a part of the
web into respective parts of the bulb and flange ribs 16, 19. The
same clinch location can be used to join the overlapped ends of the
web sections 33 to a bulb rib or a flange rib. Cross tee slots 34
are preferably punched from the side of the runners from which the
web 13 is assembled to simplify this punching operation. Hanger
holes, not shown, can be punched in the bulb rib 16 and any
overlying portion of the web 13 during the press operation. The end
connectors 14 are metal plates assembled on the ends of the bulb 11
and flange 12, preferably with the clinch shown in FIG. 6. The end
connectors 14 can be of the general type shown, for example, in
U.S. Pat. No. 6,729,100.
[0018] It is envisioned that a material savings up to about 30% can
be obtained with the serpentine web 13 as compared to constructions
having a conventional web with no large open areas. While the
foregoing disclosure involves a main runner or main tee, the
serpentine open web construction can be used to construct cross
runners. The flange can have different cross sectional
configurations other than the illustrated simple tee. Such
configurations can include a downwardly open channel, sometimes
referred to as a screw slot runner.
[0019] It should be evident that this disclosure is by way of
example and that various changes may be made by adding, modifying
or eliminating details without departing from the fair scope of the
teaching contained in this disclosure. The invention is therefore
not limited to particular details of this disclosure except to the
extent that the following claims are necessarily so limited.
* * * * *